| Abstract: | Hegu (LI 4) is one of the most frequently used and most important analgesic points in Chinese acupuncture. It is particularly effective for treating disorders of the head and face. According to the meridian theory in Traditional Chinese Medicine (TCM), the Large Intestine Meridian to which it belongs originates in the hand and terminates in the face. This theory is based, however, more on thousands of years of clinical experience rather than on scientific evidence. In our study of acupuncture effects on normal human volunteers with the non-invasive BOLD (blood oxygenation level dependant)technique for FMRI (functional magnetic resonance imaging), we demonstrated widespread effects in the brain during acupuncture at Hegu and Zusanli (ST 36). A finding of special interest was observed in the primary somatosensory cortes (SI) during Hegu acupuncture. In additlon to activation of the area representing the hand in response to the sensory impulses arising from the site of stimulation, activation also occurred in the face representation in all 3 subjects brains studied by coronal brain sections. In one of these subjects activation in the face representation was even stronger than that in the hand representation. Areas representing the neck, trunk and other parts of the upper extremity also exhibited increase in signal intensity, subject to individual variability. As compared with Hegu, such effects were either absent or much weaker with acupuncture at Zusanli (ST 36) or with other forms of sensory stimulation to the hand. Functional mapping of the brain with MRI has provided the first direct evidence in support of the important role of Hegu acupuncture in TCM. |
